<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title></title> <script> var start = Date.now() var id = setInterval(function() { var mod1El = document.querySelector('.mod1') console.log(document.querySelectorAll('div')) if (mod1El) { mod1El.innerHTML = 'mod1' clearInterval(id) } var now = Date.now() console.log(now - start, mod1El) }, 20) </script> </head> <body> <div class="adv"> <script src="http://a.baomihua.com/video/new_right_bannerD1.js"></script> </div> <div class="adv"> <script src="http://a.baomihua.com/video/inside_center_banner01.js"></script> </div> <div class="adv"> <script src="http://a.baomihua.com/video/recommend_content.js"></script> </div> <div class="adv"> <script src="http://a.baomihua.com/video/inside_center_banner02.js"></script> </div> <div class="adv"> <script src="http://a.baomihua.com/video/inside_center_banner03.js"></script> </div> <div class="mod1"></div> <div class="mod2"></div> <script> var mod2El = document.querySelector('.mod2') mod2El.innerHTML = 'mod2' console.log(Date.now() - start, mod2El) </script> <div class="mod3">mod3</div> </body> </html>